They are anaerobic cocci of the class Clostridia, with Finegoldia magna being the type species.
[1] F. magna was formerly known, along with several other Gram-positive anaerobic cocci (GPACs), as Peptostreptococcus magnus, but was moved into its own genus in 1999.
[2][3] The name is in honor of Sydney M. Finegold, an American microbiologist, while magna is Latin for large.
[3] Most surveys have found it to be susceptible to penicillins, carbapenems and metronidazole, though resistant strains have been identified.
[3][6] One review stated that "the combination of diminished antimicrobial susceptibility, its prevalence, and the described virulence factors gives F. magna a special position among the GPAC.